Tubular pile with driving cap



April 9, 1963 R. HocHsTRAssER TUBULAR PILE WITH DRIVING CAP Filed May 19, 1959 Q ...L 3.......1 .."...`v.

f@ if u,

United States Patent 3,084,518 TUBIULAE WiTiil DREVPNG CAE Robert Hochstrasscr, llehiweg 49,

Saarhrucken 3, Germany Filed May i9, 1959, Ser. No. 814,236 @iaims priority, application Germany Euiy 18, 19:58 1 Ciaim. (Cl. elw-53.58)

This invention concerns a development of the method and means for use in the driving of piles or sheet piling. It also concerns a form of steel piles particularly suitable for this purpose.

The improvement consists according to the invention in this, that the rammer used for forcing in the liquid or -semifluid mass is also used for ramming in the piles 0r sheet piling. The same blow irst forces in the liquid or mass and thereupon rams in the pile or sheet piling. The duct serving the purpose of conveying down the mass to be forced in may, where it is a question of finished concrete piles or sheeting, consists according to the invention of a pipe embedded in the concrete. in the case of steel piles or sheeting a prole may be used in accordance with the invention, which consists of two rolled and subsequently welded-together halves which enclose a central duct for the mass to be forced in and are provided with radial vanes of which, in the case of sheeting, each two are provided with the usual sheet locking means. In view of the high pressure occurring in the forcing-in duct the latter must be made correspondingly strong.

The advantages of the method and means according to the invention are as follows:

The mass to be forced in, which emerges in sudden bur-sts from the pile point exerts a clearing action and facilitates the penetration of the pile point. Furthermore, for instance where gravel or stones are present, a lubricating action between the individual stones results, which also assists the penetration of the pile point. There is the further effect in these cases, that by the mass, as it is being forced in, a certain movement between the individual stones is initiated and that therefore the immediately following pile point is better able to push the stones which are in motion aside.

A further advantage consists in this, that the immediate surroundings of the pile become saturated with forced-in mass and the friction between the pile shaft and the surrounding soil is greatly reduced during the driving-in operation. Where cement grout is used as the forced-in mass, the advantage is trebled, as during the ramrningin operation this mass exerts a lubricating effect and subsequently, after hardening, an effect which greatly increases the friction between pile and soil and in addition, where steel piles are being used, provides protection against corrosion.

In the case of piles which pass through layers containing waters or an aggressive nature liquid, a semi-fluid bituminous mass may be forced in, which will protect the pile against such waters.

The foot of the pile may be specially expanded to a certain level through so apportioning the blow of the rammer that the greatest part of the impact energy is consumed in the forcing in of concrete.

The foot expansion by the forced-in concrete allows the pile point to be made slim, which also makes the driving in operation easier.

When ramming in sheet piling which is to be later drawn again, a permanently lubricating forcing-in mass, such as a thixotropic Huid, may be used, whereby ramming and drawing of the sheet piling is made considerably easier.

The steel profile according to the invention has the "ice advantage of being easy to roll, of being well secured in the soil against buckling, on account of the relatively large side surfaces, and in the case of need causing little displacement. Where piles are to be rammed in, in the vicinity of existing foundations, the use of only as much forced-in mass is permissible in the vicinity of existing foundations as is necessary for the purpose of lubrication. By this means soil displacement and lateral pressures on the existing foundations will be reduced to a permissible amount. Vibrations caused by the ramming will also be greatly reduced, as the lubricated steel pile will require a weaker impact energy and the impact energy of each stroke will be consumed in two stages, namely, rstly by the forcing in and secondly by the actual ramming. Moreover, by using a tup of great mass, but 10W final velocity, vibrations and noise can be reduced to a minimum.

For clarifying the invention there are illustrated in the accompanying drawing diagrammatically and by way of example an arrangement in FIG. l for carrying out the new method and a steel -section in FIG. 2 according to the invention.

On the pile a-in the present instance a steel pile with a cruciform cross-section j and central forcing-in duct brests the pile cap c with the piston d and the back-pressure valve e. On the steel pile is welded a short piece of pipe j which extends loosely into the cylindrical hollow space of the pipe cap. A gasket ring g closes the cylindrical space within the pile cap. From the back-pressure valve e a pipe leads to the container h which is filled with the mass to be forced in and then put under compressed air pressure. By the compressed air pressure the mass iS forced into the cap cylinder and the duct b and the piston d raised. When the tup i falls, it iirst actuates the piston d. The back-pressure valve e closes and the trapped mass to be forced in is expelled with great force out of the pile point. After forcing in the piston d the tup i strikes on the pile cap and rams in the pile.

-I claim:

In combination, an apparatus for driving in piling comprising a pile cap for engaging the top of a pile, a chamber in the pile cap for receiving a fluent mass, a piston extending into the chamber for engagement with the uent mass and extending upwardly beyond said pile cap, a duct connected with the chamber for feeding the fluent mass into the chamber, means for preventing back pressure in the duct, a discharge duct for the fluid mass in the pile cap connected with the chamber, and a tubular pile having its upper end opening into the discharge duct, said piston and said discharge duct being substantially in alignment with said pile, whereby said pile may be driven by striking said apparatus downwardly.

References Cited in the file of this patent UNITED STATES PATENTS 1,391,678 Francois Sept. 27, 1921 1,634,231 Hiley June 28, 1927 1,978,332 Stern Oct. 23, 1934 2,779,161 Pickman Jan. 29, 1957 2,923,133 Muller Feb. 2, 1960 FOREIGN PATENTS 417,280 France Aug. 25, 1910 347,680 Germany Jan. 24, 1922 966,468 France Mar. 8, 1950 498,717 Belgium Nov. 14, 1950 991,917 France June 27, 1951 796,262 Great Britain June l1, 1958 

